A + s = 279
s = 2a
a + 2a = 279
3a = 279
a = 279/3
a = 93 <=== adult
s = 2a
s = 2(93)
s = 186 ....students
it is 3 because if it has infinte solutions than it is = to 0 and 1 and infinite solutions
Try doing A, 2/3 Hopefully it helps you, I'm not good with fractions.
Let the speed of the current equal c
and the speed of the boat in still water equal b.
b + c = 1.5 (b - c)
b + c = 1.5b - 1.5c
0.5b = 2.5c
b = 5c
The speed of the current is 1.5 mph so
b = 5 * 1.5 = 7.5 mph
She needs to score another 95 on her next test!
